Joe VO1NA wrote:

> I had to put in arguments for -S and -r which I chose at
> random ...

Thanks, that's a bug - it shouldn't need -S or -r when
sending or receiving unmodulated symbols as text.

Fixed now in version 0.2

 http://abelian.org/ebnaut/ebnaut.c

Now you can do, for example

 echo 'TEST MESSAGE' | ebnaut -et -N12 -p 4K19A  > test.txt
 ebnaut -dt -N12 -p 4K19A < test.txt

just to exercise the encoder and decoder without modulation.
Have fun with a text editor scrambling the 1's and 0's in
test.txt and watch the decoder fix the errors.

On an Intel PC you can run the Windows ebnaut-tx.exe which
works ok with wine.  This program drives the RS232 modem
control outputs.

For other computers you'll have to rig something up to read
that file of 0's and 1's and use it to drive DTR and/or RTS
on a serial port, or any of the parallel port bits, or a GPIO
pin if the computer has one (eg RPi).

If that's giving you an obstacle I can quickly rustle up a
program to do it which will work on PC and RPi.

> I send a long carrier with a phase inversion every time a 1
> is encountered,

That's a bit ambiguous, it could be taken to mean sending
differential PSK.  To be clear: send one phase for a symbol
period when the input is a 0, send the opposite phase for a
symbol period when the input is a 1.

With a transformer and a relay or diode ring, sending BPSK is
hardly any more difficult than amplitude keying.

--
Paul Nicholson
--